Gas mask equipment



T. A. O'LEARY GAS MASK EQUIPMENT April 13, 1937.

Filed NOV. 23', 1956 v IN V EN TOR.

71/0/2455 OL 14m r ATTORNEY Patented Apr. 13, 1937 UNlTED STATES PATENT OFFICE GAS MASK EQUIPMENT Thomas A. OLeary", Pittsburgh, Pa. Application November 23, 1936, Serial No. 112,236

2 Claims. 128-141) The invention relates to gas mask equipment.

In the use of gasmasksv in both military and industrial activities, a very common handicap experienced by those under physical stress for considerable periods of time is a fatigue due to the resistance to breathing occasioned by the neces-' sity of drawing air through the chemical components of the canister and the frictional resistance provided by the interior of the corrugated hose. In canisters in which filters are used of such materials, as felt, paper, and the like, this resistance is substantially greater. The object of the present invention is to provide a practical means for augmenting the flow of air through the canister to the mask, so that more air is supplied and the strain of breathing reduced. Briefly started-{this is accomplished by providing a manually operable pumping means in the hose connection between the canister and the mask. This pumping means is of such character instantly available when the necessity of an increased supply .is experienced by the wearer of the mask, and which may be utilized to clear away the condensed moisture upon the eye pieces of the mask when clouding occurs. In order to accomplish this last function, the air inlets lead to points opposite the eye pieces, as is common in the art. One embodiment of the invention is illustrated in. the accompanying drawing, where Figure 1 is a front view of a mask with the equipment applied thereto with the pumping device in section, and

Fig. 2 is a section on the line II-II of Fig. 1. Referring to the drawing, 3 is the mask, preferably of molded rubber provided with the straps l and eye pieces 5, 5 which may be of any desired construction. The lower wall of the mask is provided with the usual flutter valve 6a to permit of-the exhaust of air from the space into which the wearer of the mask exhales. Preferably formed integral with the body of the mask, is an air inlet tube 6 which branches into two parts I, I (Fig. 1), whose upper ends discharge against the lenses of the eye pieces, as indicated in Fig. 2. Air is conducted to the tube 6 through the hose connections 8, 9, the latter of which, is connected to the outlet leading from the canister l0. Such canister has a suitable air inlet, and is provided with the usual filtering means and/or chemical reaction or absorption elements. 'Located between the hose connections 8, 9 is the pumping device for augmenting the flow of air through the canister and hose connections to the mask. The device comprises a collapsible bulb or tube ll of rubber or the like connected at its ends to the tubular members I! and I3 to which the ends of the hose connections are attached. These members are preferably of hard rubber and include the disk portions l4 and I5 which are radially perforated to permit the free passage of air.

- Secured to the upper faces of the disc members by the bolts I6 and H are the discs l8 and IQ of thin flexible sheet rubber which act as check valves permitting a flow of air upward, but preventing any downward fiow.

When the tube II is collapsed by the hand bf the wearer of the equipment, a supply of air is forced upward past the valve Hi, the valve i9 preventing any back flow to the canister. When. the tube is released, it resumes its original shape, at which time air is drawn upward from the canister pastthe valve 19, the valve i8 preventing, at such time, any withdrawal of air downward through the connection 8. The tube H is located at a point where it may be most easily grasped by the operator, and is of such capacity, that a few quick operations gives the wearer substantial relief in breathing and clears the eye pieces of the mask in case they have become clouded due to condensation. The location of the tube above the canister and just below the mask provides a volume of purified air which is available the instant the pumping tube is collapsed,

so that a quick positive supply of air is forced into the mask whenever required.

It will be understood that the flexible pumping chamber may be made in a variety ofshapes and forms, and that any suitable form of check valve may be substituted for thefiap valves shown. The particular form shown is desirable because of its low resistance to the passage of air, when the pumping chamber is not being operated, and because of its freedom from any tendency to stick in closed position. The passages through the disc portions i4 and I5 are of such aggregated'capacity that there is no throttling of the fiow of air through the pumping device when such device is not being operated. Although it is preferred to locate the check valves, in the end closure members of the pumping chamber, it is feasible to place them at other points in the hose connections above and below the chamber.

What I claim is:, I air inlet line from the canister to the mask, a 1. In combination, a gas mask, a canister, flexible pumping chamber located in the inlet an air inlet line from the canister to the mask, line beween the canister and mask, and a pair a flexible pumping chamber located in the inlet of check valves at the opposite ends of the pump- 5 line between the canister and mask, and a pair ing chamber, both opening toward the mask, the 5 of check valves at the opposite ends of the pumpair inlet line being arranged to discharge against ins chamber, both opening toward the mask. the eye pieces 01' the mask.

2. In combination. a gas mask, a canister, an THOMAS A. OIEARY. 

